Project Description
The keys in db or mok can be used to verify boot loader and kernel binary for booting. But upstream kernel doesn't trust them for enrolling to trusted keyring because they are enrolled outside the boundaries of kernel. Which means that IMA can not use db/mok keys for verification.
Currently if users/partners want to enroll their keys to the kernel trusted keyring, the user key must be signed by kernel's build-in key. But SUSE will not sign any user key. In upstream, there have some known technologies against this situation:
CONFIGSYSTEMEXTRA_CERTIFICATE Reserve a space in kernel binary for enrolling user's key.
MokListTrustedRT A new MOK variable be introduced. User can use this variable to tell shim and kernel that the keys in MOK can be trusted by kernel. Which means keys will be enrolled to trusted keyring.
Goal for this Hackweek
Find a good way for SLE/openSUSE user for enrolling their key to trust keyring in kernel. IMA should also trust those keys.
Resources
kernel, shim, mokutil
This project is part of:
Hack Week 21
Activity
Comments
-
over 2 years ago by jzerebecki | Reply
Thank you, good to know. This would make SecureBoot useful for me. Seems MokListTrustedRT is supported since kernel v5.18-rc1: https://github.com/torvalds/linux/blob/eaa54b1458ca84092e513d554dd6d234245e6bef/security/integrity/platformcerts/machinekeyring.c#L57 And since shim 15.5-rc2: https://github.com/rhboot/shim/commit/4e513405b4f1641710115780d19dcec130c5208f
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